VIENNA — Vienna's a fabled city for spying – and now its cloak-and-dagger legend has a 21st-century twist.

A stately villa in a leafy district of the Austrian capital is at the center of a ruckus over whether the NSA is snooping on the city's residents, with allegations flying that the building serves as a sophisticated a U.S. intelligence listening post.

Both the U.S. and Austrian governments deny reports claiming to expose a major surveillance operation by the National Security Agency from within the towers of the sprawling manor. They say the building is nothing more than an "Open Source Center" evaluating information freely available in newspapers and on the Internet – albeit one run by the CIA.

Many are skeptical in a country shocked by revelations by NSA leaker Edward Snowden that the organization has been able to spy on the online activities of millions around the world. The Viennese are also mindful of the city's Cold War reputation as the spying capital of the world – an outpost for eavesdropping by both sides of the divide.

With passions high over the NSA, Austrians question the need for any kind of U.S. intelligence gathering in their capital, including open source centers.

"Whatever it is, it's confirmation of intelligence agency activity in Vienna," said activist Rudolf Fussi, whose recently organized demonstration in front of the building drew over 200 people.

He said the government is guilty of cooperating with a foreign intelligence service, a crime punishable by a prison term, by allowing such activities and protecting the building with police.

Austria's Kurier newspaper reported this week that the U.S. government had decided to end operations at the site within a year or two – and suggested that was because its cover was blown. CIA spokesman Edward Price refused comment in an email to The Associated Press Thursday.

Meanwhile, the allegations have turned into an Austrian affair of state.

Green party member Peter Pilz says Austria's National Security Council will convene in the next few weeks to discuss what went on inside the building after opposition parties and even some government coalition members called for such a meeting.

The affair is also straining the government coalition, comprised of center-right and center-left forces. The conservative-run Interior Ministry denies cooperation with the NSA and suggests that – if there is any such collaboration – it must come from the Defense Ministry, run by the rival party.

Defense Minister Gerhard Klug has yet to comment on the allegations. But Pilz, who sits on Parliament's security and intelligence committee, asserts that intelligence services run by both ministries work with and protect the NSA.

The villa is "clearly a U.S. intelligence center and according to our information NSA," he says, citing unnamed Austrian government officials as his source.